Presently, it is known to deliver the output beam exiting from a laser system to an intended target using an articulated arm attached to the laser system. An articulated arm is a series of straight segments connected together by rotatable joints. A mirror is placed at each joint such that the laser beam travelling down each of the segments is re-directed down the subsequent segment. The beam is incident on the surface of each mirror at an angle of 45.degree..
Recently, high power, multiple wavelength laser systems have been developed, whereby the traditional articulated arm has become inadequate for laser beam delivery. While broadband coatings can be used on the mirrors at each joint, such coatings are very difficult to develop. Broadband reflective coatings tend to have a lower damage threshold than other coatings, which will then fail when used to reflect higher power laser beams. Further, the broadband coating design is complicated by the fact that the beam is incident upon the reflecting surface at an angle at 45.degree.. Lastly, reflections at such an angle tend to reflect the S and P polarizations of the beam differently.
There is a need for a laser beam delivery system that delivers a high powered, multi-wavelength laser beam with the flexibility of an articulated arm without adversely affecting the S and P polarizations of the laser beam.